title: A molecular update on pseudohypoaldosteronism type II.
abstract: The DCT (distal convoluted tubule) is the site of microregulation of water reabsorption and ion handling in the kidneys, which is mainly under the control of aldosterone. Aldosterone binds to and activates mineralocorticoid receptors, which ultimately lead to increased sodium reabsorption in the distal part of the nephron. Impairment of mineralocorticoid signal transduction results in resistance to aldosterone and mineralocorticoids, and, therefore, causes disturbances in electrolyte balance. Pseudohypoaldosteronism type II (PHAII) or familial hyperkalemic hypertension (FHHt) is a rare, autosomal dominant syndrome characterized by hypertension, hyperkalemia, metabolic acidosis, elevated or low aldosterone levels, and decreased plasma renin activity. PHAII is caused by mutations in the WNK isoforms (with no lysine kinase), which regulate the Na-Cl and Na-K-Cl cotransporters (NCC and NKCC2, respectively) and the renal outer medullary potassium (ROMK) channel in the DCT. This review focuses on new candidate genes such as KLHL3 and Cullin3, which are instrumental to unraveling novel signal transductions pathways involving NCC, to better understand the cause of PHAII along with the molecular mechanisms governing the pathophysiology of PHAII and its clinical manifestations.
authors.affiliation: 286, Dept. of Physiology, Radboud Univ. Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands. r.bindels@fysiol.umcn.nl.
authors.forename: Ganesh
authors.initials: G
authors.lastname: Pathare
authors.forename: Joost G J
authors.initials: JG
authors.lastname: Hoenderop
authors.forename: René J M
authors.initials: RJ
authors.lastname: Bindels
authors.forename: Pedro
authors.initials: P
authors.lastname: San-Cristobal
mesh_terms: D000818:Animals; D053503:Epithelial Sodium Channels / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D007686:Kidney Tubules, Distal / Q000378:metabolism*; D011546:Pseudohypoaldosteronism / Q000209:etiology / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D064486:Solute Carrier Family 12, Member 3 / Q000378:metabolism*
chemical_list: D053503:Epithelial Sodium Channels; D047908:Intracellular Signaling Peptides and Proteins; D064486:Solute Carrier Family 12, Member 3
keywords: WNK; aldosterone; distal convoluted tubule; epithelial sodium channel; thiazide-sensitive Na-Cl cotransporter